package org.slf4j;
|
|
import com.alibaba.ttl.TransmittableThreadLocal;
|
import org.slf4j.spi.MDCAdapter;
|
|
import java.util.Collections;
|
import java.util.HashMap;
|
import java.util.Map;
|
import java.util.Set;
|
|
/**
|
* 石家庄喜高科技有限责任公司 版权所有 © Copyright 2020<br>
|
*
|
* @Description: 重构{@link LogbackMDCAdapter}类，搭配TransmittableThreadLocal实现父子线程之间的数据传递<br>
|
* @Project: <br>
|
* @CreateDate: Created in 2020/2/4 16:05 <br>
|
* @Author: <a href="4345453@kidgrow.com">liuke</a>
|
*/
|
public class TtlMDCAdapter implements MDCAdapter {
|
private final ThreadLocal<Map<String, String>> copyOnInheritThreadLocal = new TransmittableThreadLocal<>();
|
|
private static final int WRITE_OPERATION = 1;
|
private static final int MAP_COPY_OPERATION = 2;
|
|
private static TtlMDCAdapter mtcMDCAdapter;
|
|
/**
|
* keeps track of the last operation performed
|
*/
|
private final ThreadLocal<Integer> lastOperation = new ThreadLocal<>();
|
|
static {
|
mtcMDCAdapter = new TtlMDCAdapter();
|
MDC.mdcAdapter = mtcMDCAdapter;
|
}
|
|
public static MDCAdapter getInstance() {
|
return mtcMDCAdapter;
|
}
|
|
private Integer getAndSetLastOperation(int op) {
|
Integer lastOp = lastOperation.get();
|
lastOperation.set(op);
|
return lastOp;
|
}
|
|
private static boolean wasLastOpReadOrNull(Integer lastOp) {
|
return lastOp == null || lastOp == MAP_COPY_OPERATION;
|
}
|
|
private Map<String, String> duplicateAndInsertNewMap(Map<String, String> oldMap) {
|
Map<String, String> newMap = Collections.synchronizedMap(new HashMap<>());
|
if (oldMap != null) {
|
// we don't want the parent thread modifying oldMap while we are
|
// iterating over it
|
synchronized (oldMap) {
|
newMap.putAll(oldMap);
|
}
|
}
|
|
copyOnInheritThreadLocal.set(newMap);
|
return newMap;
|
}
|
|
/**
|
* Put a context value (the <code>val</code> parameter) as identified with the
|
* <code>key</code> parameter into the current thread's context map. Note that
|
* contrary to log4j, the <code>val</code> parameter can be null.
|
* <p/>
|
* <p/>
|
* If the current thread does not have a context map it is created as a side
|
* effect of this call.
|
*
|
* @throws IllegalArgumentException in case the "key" parameter is null
|
*/
|
@Override
|
public void put(String key, String val) {
|
if (key == null) {
|
throw new IllegalArgumentException("key cannot be null");
|
}
|
|
Map<String, String> oldMap = copyOnInheritThreadLocal.get();
|
Integer lastOp = getAndSetLastOperation(WRITE_OPERATION);
|
|
if (wasLastOpReadOrNull(lastOp) || oldMap == null) {
|
Map<String, String> newMap = duplicateAndInsertNewMap(oldMap);
|
newMap.put(key, val);
|
} else {
|
oldMap.put(key, val);
|
}
|
}
|
|
/**
|
* Remove the the context identified by the <code>key</code> parameter.
|
* <p/>
|
*/
|
@Override
|
public void remove(String key) {
|
if (key == null) {
|
return;
|
}
|
Map<String, String> oldMap = copyOnInheritThreadLocal.get();
|
if (oldMap == null) {
|
return;
|
}
|
|
Integer lastOp = getAndSetLastOperation(WRITE_OPERATION);
|
|
if (wasLastOpReadOrNull(lastOp)) {
|
Map<String, String> newMap = duplicateAndInsertNewMap(oldMap);
|
newMap.remove(key);
|
} else {
|
oldMap.remove(key);
|
}
|
|
}
|
|
|
/**
|
* Clear all entries in the MDC.
|
*/
|
@Override
|
public void clear() {
|
lastOperation.set(WRITE_OPERATION);
|
copyOnInheritThreadLocal.remove();
|
}
|
|
/**
|
* Get the context identified by the <code>key</code> parameter.
|
* <p/>
|
*/
|
@Override
|
public String get(String key) {
|
final Map<String, String> map = copyOnInheritThreadLocal.get();
|
if ((map != null) && (key != null)) {
|
return map.get(key);
|
} else {
|
return null;
|
}
|
}
|
|
/**
|
* Get the current thread's MDC as a map. This method is intended to be used
|
* internally.
|
*/
|
public Map<String, String> getPropertyMap() {
|
lastOperation.set(MAP_COPY_OPERATION);
|
return copyOnInheritThreadLocal.get();
|
}
|
|
/**
|
* Returns the keys in the MDC as a {@link Set}. The returned value can be
|
* null.
|
*/
|
public Set<String> getKeys() {
|
Map<String, String> map = getPropertyMap();
|
|
if (map != null) {
|
return map.keySet();
|
} else {
|
return null;
|
}
|
}
|
|
/**
|
* Return a copy of the current thread's context map. Returned value may be
|
* null.
|
*/
|
@Override
|
public Map<String, String> getCopyOfContextMap() {
|
Map<String, String> hashMap = copyOnInheritThreadLocal.get();
|
if (hashMap == null) {
|
return null;
|
} else {
|
return new HashMap<>(hashMap);
|
}
|
}
|
|
@Override
|
public void setContextMap(Map<String, String> contextMap) {
|
lastOperation.set(WRITE_OPERATION);
|
|
Map<String, String> newMap = Collections.synchronizedMap(new HashMap<>());
|
newMap.putAll(contextMap);
|
|
// the newMap replaces the old one for serialisation's sake
|
copyOnInheritThreadLocal.set(newMap);
|
}
|
}
|
